<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, user-scalable=no,initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <title>Document</title>
    <style type="text/css">
    /*retina屏幕适配 通过样式将它的尺寸设置为原来的一半*/
        .shipei{
            width: 300px;
            height: 215px;
        }

    </style>
</head>
<body>
    <img src="images/pic1x.jpg" alt="1倍图">
    <img src="images/pic2x.jpg" alt="2倍图" class="shipei">

</body>
</html>